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diff --git a/t/async_examples/async_tailer.ru b/t/async_examples/async_tailer.ru
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+++ b/t/async_examples/async_tailer.ru
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+#!/usr/bin/env rackup -s thin
+#
+#  async_tailer.ru
+#  raggi/thin
+#
+#  Tested with 150 spawned tails on OS X
+#
+#  Created by James Tucker on 2008-06-18.
+#  Copyright 2008 James Tucker <raggi@rubyforge.org>.
+
+# Uncomment if appropriate for you..
+# EM.epoll
+# EM.kqueue
+
+tail_log_file = ENV["TAIL_LOG_FILE"] or abort "TAIL_LOG_FILE= env must be set"
+unless ::File.file?(tail_log_file) && ::File.readable?(tail_log_file)
+  abort "#{tail_log_file} must be a readable regular file"
+end
+
+class DeferrableBody
+  include EventMachine::Deferrable
+
+  def initialize
+    @queue = []
+    # make sure to flush out the queue before closing the connection
+    callback{
+      until @queue.empty?
+        @queue.shift.each{|chunk| @body_callback.call(chunk) }
+      end
+    }
+  end
+
+  def schedule_dequeue
+    return unless @body_callback
+    EventMachine::next_tick do
+      next unless body = @queue.shift
+      body.each do |chunk|
+        @body_callback.call(chunk)
+      end
+      schedule_dequeue unless @queue.empty?
+    end
+  end
+
+  def call(body)
+    @queue << body
+    schedule_dequeue
+  end
+
+  def each &blk
+    @body_callback = blk
+    schedule_dequeue
+  end
+
+end
+
+module TailRenderer
+  attr_accessor :callback
+
+  def receive_data(data)
+    @callback.call([data])
+  end
+
+  def unbind
+    @callback.succeed
+  end
+end
+
+class AsyncTailer
+
+  AsyncResponse = [-1, {}, []].freeze
+
+  def call(env)
+
+    body = DeferrableBody.new
+
+    EventMachine::next_tick do
+
+      env['async.callback'].call [200, {'Content-Type' => 'text/html'}, body]
+
+      body.call ["<h1>Async Tailer</h1><pre>"]
+
+    end
+
+    EventMachine::popen("tail -f #{ENV["TAIL_LOG_FILE"]}", TailRenderer) do |t|
+
+      t.callback = body
+
+      # If for some reason we 'complete' body, close the tail.
+      body.callback do
+        t.close_connection
+      end
+
+      # If for some reason the client disconnects, close the tail.
+      body.errback do
+        t.close_connection
+      end
+
+    end
+
+    AsyncResponse
+  end
+
+end
+
+run AsyncTailer.new